Enclosures for housing electronic circuit boards are widely used in a variety of technologies, including telecommunications, industrial control, medical electronics and military applications. Such enclosures are provided with individual bays having guides so that individual circuit boards can be slid into and out of the bays, and a backplane through which the circuit boards in respective bays may be electrically connected to other electronic components.
The electronic components on the printed circuit boards generate heat, which should be removed in order to prevent failure of the printed circuit boards within the enclosure. One method of heat removal is through conduction cooling, where heat is diffused through components in the printed circuit boards and the enclosure independently of any air circulation. It is known to provide a heat sink, called a cold plate, as part of enclosure bays. The assembly including the printed circuit boards also includes a heat exchanger, called a vapor chamber. In operation, a printed circuit board assembly is inserted along an axis (e.g., the x-axis). Guides within the enclosure bays then guide the printed circuit board assembly in along the x-axis and orthogonally upward (e.g., along the y-axis), attempting to bring the vapor chamber into physical contact with the cold plate.
While cold plates and vapor chambers are commonly used for conducting heat away from the printed circuit boards, such conventional systems suffer a drawback in that it is difficult to establish good contact between a vapor chamber on the printed circuit board assembly with the cold plate in the enclosure bay. Heat conduction falls off with a space between the vapor chamber and cold plate, and it is critical to establish a good, tight contact between the vapor chamber and cold plate. One cause of the poor contact between the cold plate and vapor chamber in conventional designs is that the contact interface between the vapor chamber and cold plate is parallel to the insertion direction of the printed circuit board assembly. Thus, it is difficult to establish the requisite force between the cold plate and vapor chamber for good thermal conductivity.